[GFS2] Update journal accounting code.

A small update to the journaling code to change the way that
the "extra" blocks are accounted for in the journal. These are
used at a rate of one per 503 metadata blocks or one per 251
journaled data blocks (or just one if the total number of journaled
blocks in the transaction is smaller). Since we are using them at
two different rates the old method of accounting for them no longer
works and we count them up as required.

Since the "per transaction" accounting can't handle this (there is no
fixed number of header blocks per transaction) we have to account for
it in the general journal code. We now require that each transaction
reserves more blocks than it actually needs to take account of the
possible extra blocks.

Also a final fix to dir.c to ensure that all ref counts are handled
correctly.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

fs/gfs2/dir.c

@@ -776,9 +776,9 @@ static struct gfs2_dirent *gfs2_dirent_search(struct inode *inode,
 				goto got_dent;
 			leaf = (struct gfs2_leaf *)bh->b_data;
 			ln = be64_to_cpu(leaf->lf_next);
+			brelse(bh);
 			if (!ln)
 				break;
-			brelse(bh);
 			error = get_leaf(ip, ln, &bh);
 		} while(!error);
 
@@ -790,7 +790,7 @@ static struct gfs2_dirent *gfs2_dirent_search(struct inode *inode,
 		return ERR_PTR(error);
 	dent = gfs2_dirent_scan(inode, bh->b_data, bh->b_size, scan, name, NULL);
 got_dent:
-	if (unlikely(IS_ERR(dent))) {
+	if (unlikely(dent == NULL || IS_ERR(dent))) {
 		brelse(bh);
 		bh = NULL;
 	}
@@ -1477,7 +1477,6 @@ int gfs2_dir_search(struct inode *dir, const struct qstr *name,
 		brelse(bh);
 		return 0;
 	}
-	brelse(bh);
 	return -ENOENT;
 }
 
@@ -1619,7 +1618,6 @@ int gfs2_dir_del(struct gfs2_inode *dip, const struct qstr *name)
 	   previous entry otherwise */
 	dent = gfs2_dirent_search(dip->i_vnode, name, gfs2_dirent_prev, &bh);
 	if (!dent) {
-		brelse(bh);
 		gfs2_consist_inode(dip);
 		return -EIO;
 	}
@@ -1680,7 +1678,6 @@ int gfs2_dir_mvino(struct gfs2_inode *dip, const struct qstr *filename,
 
 	dent = gfs2_dirent_search(dip->i_vnode, filename, gfs2_dirent_find, &bh);
 	if (!dent) {
-		brelse(bh);
 		gfs2_consist_inode(dip);
 		return -EIO;
 	}
@@ -1961,7 +1958,6 @@ int gfs2_diradd_alloc_required(struct inode *inode,
 
 	dent = gfs2_dirent_search(inode, name, gfs2_dirent_find_space, &bh);
 	if (!dent) {
-		brelse(bh);
 		return 1;
 	}
 	if (IS_ERR(dent))

fs/gfs2/log.c

@@ -412,11 +412,13 @@ static void log_flush_commit(struct gfs2_sbd *sdp)
 	struct list_head *head = &sdp->sd_log_flush_list;
 	struct gfs2_log_buf *lb;
 	struct buffer_head *bh;
+#if 0
 	unsigned int d;
 
 	d = log_distance(sdp, sdp->sd_log_flush_head, sdp->sd_log_head);
 
 	gfs2_assert_withdraw(sdp, d + 1 == sdp->sd_log_blks_reserved);
+#endif
 
 	while (!list_empty(head)) {
 		lb = list_entry(head->next, struct gfs2_log_buf, lb_list);
@@ -483,6 +485,7 @@ void gfs2_log_flush(struct gfs2_sbd *sdp, struct gfs2_glock *gl)
 	sdp->sd_log_head = sdp->sd_log_flush_head;
 
 	/* printk(KERN_INFO "sd_log_num_hdrs %u\n", sdp->sd_log_num_hdrs); */
+	sdp->sd_log_blks_free -= sdp->sd_log_num_hdrs;
 
 	sdp->sd_log_blks_reserved =
 		sdp->sd_log_commited_buf =
@@ -515,8 +518,7 @@ static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
 	gfs2_assert_withdraw(sdp, ((int)sdp->sd_log_commited_revoke) >= 0);
 
 	if (sdp->sd_log_commited_buf)
-		reserved += 1 + sdp->sd_log_commited_buf +
-			    sdp->sd_log_commited_buf/503;
+		reserved += sdp->sd_log_commited_buf;
 	if (sdp->sd_log_commited_revoke)
 		reserved += gfs2_struct2blk(sdp, sdp->sd_log_commited_revoke,
 					    sizeof(uint64_t));
@@ -527,7 +529,8 @@ static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr)
 
 	gfs2_assert_withdraw(sdp, sdp->sd_log_blks_free >= old);
 	gfs2_assert_withdraw(sdp,
-			     sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks);
+			     sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks +
+			     sdp->sd_log_num_hdrs);
 
 	sdp->sd_log_blks_reserved = reserved;
 
@@ -582,6 +585,7 @@ void gfs2_log_shutdown(struct gfs2_sbd *sdp)
 
 	log_write_header(sdp, GFS2_LOG_HEAD_UNMOUNT, 0);
 
+	/* printk(KERN_INFO "sd_log_blks_free %u, sd_jdesc->jd_blocks %u\n", sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks); */
 	gfs2_assert_withdraw(sdp, sdp->sd_log_blks_free ==
 			     sdp->sd_jdesc->jd_blocks);
 	gfs2_assert_withdraw(sdp, sdp->sd_log_head == sdp->sd_log_tail);

fs/gfs2/trans.c

@@ -44,7 +44,7 @@ int gfs2_trans_begin(struct gfs2_sbd *sdp, unsigned int blocks,
 	tr->tr_revokes = revokes;
 	tr->tr_reserved = 1;
 	if (blocks)
-		tr->tr_reserved += 1 + blocks;
+		tr->tr_reserved += 6 + blocks;
 	if (revokes)
 		tr->tr_reserved += gfs2_struct2blk(sdp, revokes,
 						   sizeof(uint64_t));
@@ -83,20 +83,15 @@ int gfs2_trans_begin(struct gfs2_sbd *sdp, unsigned int blocks,
 
 void gfs2_trans_end(struct gfs2_sbd *sdp)
 {
-	struct gfs2_trans *tr;
+	struct gfs2_trans *tr = current->journal_info;
 
-	tr = current->journal_info;
+	BUG_ON(!tr);
 	current->journal_info = NULL;
 
-	if (gfs2_assert_warn(sdp, tr))
-		return;
-
 	if (!tr->tr_touched) {
 		gfs2_log_release(sdp, tr->tr_reserved);
-
 		gfs2_glock_dq(&tr->tr_t_gh);
 		gfs2_holder_uninit(&tr->tr_t_gh);
-
 		kfree(tr);
 		return;
 	}
@@ -113,10 +108,8 @@ void gfs2_trans_end(struct gfs2_sbd *sdp)
 	}
 
 	gfs2_log_commit(sdp, tr);
-
         gfs2_glock_dq(&tr->tr_t_gh);
         gfs2_holder_uninit(&tr->tr_t_gh);
-
         kfree(tr);
 
 	if (sdp->sd_vfs->s_flags & MS_SYNCHRONOUS)